Watch out for more and more devices including VoIP capabilities. Faster embedded processors from the likes of ARM and MIPS are enabling work that would normally be offloaded to a specialist DSP (digital signal processor) chip to be done on the main processor instead.
It's only practical at the low end of the market - any serious or enterprise-quality VoIP router is still likely to have a DSP. But "soft DSP" technology such as D2's vPort does open up a number of possibilities.
One is that it takes out cost - a DSP adds $5 or $10, plus it means a bigger, more complex circuit board, and two development toolkits (one for the CPU, one for the DSP) instead of one. So eliminating it means cheaper VoIP routers and IP telephony adapters, which in turn means more VoIP customers.
The other is that existing devices such as wireless APs, security devices and the like may already have the spare horsepower to be retrofitted with VoIP. They'll still need handsets of course, but it's yet another way of spreading that VoIP goodness around.
Are you ready for managing all that?